Sleeping bag attachment system

ABSTRACT

A sleeping bag comprises first and second halves and an entrance end having an entrance aperture. At the entrance end, a first member attachment zipper half extends across the first half, and a second member attachment zipper half extends across the second half. A detachable pillow sleeve can be removably secured to the sleeping bag by securing a pillow sleeve attachment zipper half on the detachable pillow sleeve to either the first or second member attachment zipper half. The pillow sleeve also has a first hood attachment zipper half, and a detachable hood can be removably secured to the pillow sleeve by securing a second hood attachment zipper half on the hood to the first hood attachment zipper half. The hood can also be secured directly to the sleeping bag by securing the second hood attachment zipper half to either the first or second member attachment zipper half.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from U.S. Provisional Patent Application No. 61/071,051 filed on Apr. 9, 2008, the teachings of which are incorporated herein by reference in their entirety.

FIELD OF INVENTION

The present invention relates to sleeping bag systems, and more particularly to sleeping bag systems that can be adapted to a variety of situations.

BACKGROUND OF THE INVENTION

Camping is a popular activity for a wide variety of people. While some people choose to camp only in the summer months, others camp in the spring and fall, and some camp all year round, including winter.

In certain climates, there are substantial differences between winter and summer temperatures, such that a sleeping bag designed for summer may provide inadequate insulation during the winter, while a sleeping bag that is designed to provide adequate warmth during the winter may prove to be hot and uncomfortable during the summer months

One solution has been to simply “nest” two lighter sleeping bags, one inside the other, during the winter months. However, this requires the purchase of two sleeping bags, and is less than an ideal solution.

In addition, people often have different tastes in terms of how much they want to “rough it” when camping, and how much comfort they wish their sleeping bag to provide.

SUMMARY OF THE INVENTION

In one aspect, the present invention is directed to a sleeping bag. The sleeping bag comprises first and second opposed halves defining a sleeping compartment therebetween, and has an entrance aperture at an entrance end of the sleeping bag. The entrance aperture opens into the sleeping compartment. A first member attachment zipper half extends across the first opposed half at the entrance end, and a second member attachment zipper half extends across the second opposed half at the entrance end.

In a particular embodiment, a draft collar extends across the entrance aperture inwardly of the entrance end, and the first member attachment zipper half and the second member attachment zipper half are located adjacent the draft collar, between the draft collar and the entrance end.

A sleeping bag as described above may form part of a sleeping bag system, which system also includes a detachable pillow sleeve. The detachable pillow sleeve has a pillow sleeve attachment zipper half extending along one edge of the detachable pillow sleeve. The pillow sleeve attachment zipper half mates with the first member attachment zipper half and with the second member attachment zipper half. The pillow sleeve also has a first hood attachment zipper half adjacent and substantially parallel to the pillow sleeve attachment zipper half.

The sleeping bag system may further comprise a detachable hood. The detachable hood has a second hood attachment zipper half extending along a base edge of the detachable hood, which mates with the first hood attachment zipper half and with the first member attachment zipper half and with the second member attachment zipper half.

In a particular embodiment, a sleeping bag as described above may further comprise an entrance aperture zipper. The entrance aperture zipper comprises a first entrance aperture zipper half extending at least partially along an edge of the first opposed half and a second entrance aperture zipper half extending at least partially along an edge of the second opposed half. The first and second entrance aperture zipper halves mate with one another for selectably enlarging and constricting the entrance aperture.

In another aspect, the present invention is directed to a detachable pillow sleeve. The detachable pillow sleeve has a pillow sleeve attachment zipper half extending along one edge thereof, and a hood attachment zipper half adjacent and substantially parallel to the pillow sleeve attachment zipper half. Cushioning may be disposed inside the detachable pillow sleeve.

In a further aspect, the present invention is directed to a sleeping bag system. The sleeping bag system comprises a first sleeping bag having a first length and a second sleeping bag having a second length that is different from the first length. Each sleeping bag comprises first and second opposed sleeping bag halves defining respective sleeping compartments therebetween, and each sleeping bag has an entrance aperture at an entrance end thereof which opens into the respective sleeping compartment. Each sleeping bag further comprises an entrance aperture zipper comprising a first entrance aperture zipper half extending at least partially along an edge of the first opposed half and a second entrance aperture zipper half extending at least partially along an edge of the second opposed half. The first and second entrance aperture zipper halves mate with one another for selectably enlarging and constricting the respective entrance aperture. Each entrance aperture zipper is of equal length, and each first entrance aperture zipper half mates with the second entrance aperture zipper half of the other sleeping bag.

In a still further aspect, the present invention is directed to a sleeping bag system. The sleeping bag system comprises a sleeping bag, a detachable pillow sleeve, a detachable hood, and a detachable layer.

The sleeping bag comprises first and second opposed halves defining a sleeping compartment therebetween, and a sleeping bag entrance aperture at an entrance end of the sleeping bag, with the sleeping bag entrance aperture opening into the sleeping compartment. A first member attachment zipper half extends across the first opposed half at the entrance end, and a second member attachment zipper half extends across the second opposed half at the entrance end. A first layer attachment zipper half extends across the first opposed half at the entrance end, inwardly of the first member attachment zipper half, and a second layer attachment zipper half extends across the second opposed half at the entrance end, inwardly of the second member attachment zipper half. The sleeping bag also has a sleeping bag entrance aperture zipper comprising a first sleeping bag entrance aperture zipper half extending at least partially along an edge of the first opposed half and a second sleeping bag entrance aperture zipper half extending at least partially along an edge of the second opposed half. The first and second sleeping bag entrance aperture zipper halves mate with one another for selectably enlarging and constricting the sleeping bag entrance aperture.

The detachable pillow sleeve has a pillow sleeve attachment zipper half extending along one edge of the detachable pillow sleeve, which mates with the first member attachment zipper half and with the second member attachment zipper half, and also has a first hood attachment zipper half adjacent and substantially parallel to the pillow sleeve attachment zipper half.

The detachable hood has a second hood attachment zipper half extending along a base edge of the detachable hood, which mates with the first hood attachment zipper half and with the first member attachment zipper half and with the second member attachment zipper half.

The detachable layer defines an enclosure having a layer entrance aperture that is extended by a slit along a side of the detachable layer, and is sized to fit within the sleeping compartment of the sleeping bag to be substantially coterminous with the sleeping bag. The detachable layer has first and second layer zipper halves extending along opposed edges of the layer entrance aperture, with the first layer zipper half mating with the first layer attachment zipper half, and the second layer zipper half mating with the second layer attachment zipper half. When the first layer zipper half is mated with the first layer attachment zipper half and the second layer zipper half is mated with the second layer attachment zipper half, the layer entrance aperture is aligned with the sleeping bag entrance aperture and the slit extending the layer entrance aperture is aligned with the sleeping bag entrance aperture zipper.

In one embodiment of the sleeping bag system, the first and second layer zipper halves each also mate with the pillow sleeve attachment zipper half and the second hood attachment zipper half.

The present invention is also directed to methods for using the above-described apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings wherein:

FIG. 1 shows an exemplary embodiment of a sleeping bag in a partially open position, in accordance with an aspect of the present invention;

FIG. 1A shows a more detailed cross-sectional view of a portion of the sleeping bag of FIG. 1;

FIG. 2 shows the sleeping bag of FIG. 1, together with a detachable layer, in accordance with an aspect of the present invention;

FIG. 2A shows the detachable layer of FIG. 2 inside of the sleeping bag of FIG. 1;

FIG. 3 shows a more detailed view of a portion of the sleeping bag of FIG. 2A including a zipper slider, in accordance with an aspect of the present invention;

FIG. 3A shows a detailed view of an extension flap covering the zipper slider of FIG. 3, in accordance with an aspect of the present invention;

FIG. 4 shows the sleeping bag of FIG. 1 in a closed position, in accordance with an aspect of the present invention;

FIG. 5 shows an entrance end of the sleeping bag of FIG. 1 with a detachable pillow sleeve and detachable hood prepared for attachment to the sleeping bag, in accordance with an aspect of the present invention;

FIG. 5A shows an entrance end of the sleeping bag of FIG. 1 with a detachable pillow sleeve secured thereto;

FIG. 5B shows an entrance end of the sleeping bag of FIG. 1 with a detachable hood secured thereto;

FIG. 6 shows the entrance end of the sleeping bag of FIG. 1 with the detachable pillow sleeve of FIG. 5 secured thereto and the detachable hood of FIG. 5 secured to the detachable pillow sleeve, and also shows insertion of a pillow into the pillow sleeve, in accordance with an aspect of the present invention;

FIG. 6A shows a more detailed view of certain portions of certain zippers shown in FIG. 6, in accordance with an aspect of the present invention;

FIG. 7 shows a detachable sleeping bag layer, and illustrates attachment of a detachable pillow sleeve thereto and attachment of a detachable hood to the detachable pillow sleeve, in accordance with an aspect of the present invention;

FIG. 8 shows two sleeping bags attached to one another in a side-by-side arrangement, in accordance with an aspect of the present invention;

FIG. 9A shows the two sleeping bags of FIG. 8, each with a detachable pillow sleeve attached thereto and each detachable pillow sleeve having a detachable hood attached thereto, in accordance with an aspect of the present invention; and

FIG. 9B shows two sleeping bags of dissimilar length attached to one another in a side-by-side arrangement, each with a detachable pillow sleeve attached thereto and each detachable pillow sleeve having a detachable hood attached thereto, in accordance with an aspect of the present invention.

DETAILED DESCRIPTION

With reference now to FIG. 1, an exemplary sleeping bag according to an aspect of the present invention is shown generally at 10. The sleeping bag 10 is shown in FIG. 1 in a partially open position, and may be considered conceptually to have an entrance end denoted generally by the reference numeral 12, and a lower end denoted generally by the reference numeral 14. The entrance end 12 corresponds to the end of the sleeping bag 10 which is intended to receive a user's head and upper body, and the lower end 14 corresponds to the end of the sleeping bag 10 that is intended to receive a user's feet. The entrance end 12 is the end of the sleeping bag 10 at which the user will enter the sleeping compartment of the sleeping bag 10. The sleeping bag 10 has a first half 16 and a second half 18 arranged in opposed facing relation so that the first half 16 and the second half 18 overlap one another to define the sleeping compartment therebetween. The first half 16 can be the bottom of the sleeping bag 10 (i.e. the portion that engages the sleeping surface) and the second half 18 can be the top, as shown herein, or alternatively the first half 16 can be the top of the sleeping bag 10 and the second half 18 can be the bottom, so that a user can select the relative side (left or right) by which the interior of the sleeping bag 10 is accessed. In the particular embodiment illustrated herein, the sleeping bag 10 is a semi-rectangular sleeping bag, that is, the sleeping bag 10 has a semi-rectangular shape when in the closed position shown in FIG. 4. Other suitable shapes may also be used.

Continuing to refer to FIG. 1, the sleeping bag 10 comprises a main sheet 28 which forms the first and second halves 16, 18, first and second draft tubes 30 and 32, and a draft collar 34. The draft collar 34 extends across the entrance aperture inwardly of the entrance end 12. An entrance aperture zipper 36 comprises a first entrance aperture zipper half 36A extending at least partially along an edge of the first opposed half 16 and a second entrance aperture zipper half 36B extending at least partially along an edge of the second opposed half 18.

When the entrance aperture zipper 36 is opened it enlarges the entrance aperture at the entrance end 12; when the entrance aperture zipper 36 is closed it restricts the entrance aperture. Thus, the first and second entrance aperture zipper halves 36A, 36B mate with one another for selectably enlarging and constricting the entrance aperture. The entrance aperture zipper 36 runs part way down the side 15 of the sleeping bag 10 from the entrance end 12. In particular, the first entrance aperture zipper half 36A runs along part of the side 15 of the first half 16 of the sleeping bag 10, and the second entrance aperture zipper half 36B runs along part of the side 15 of the second half 18 of the sleeping bag 10. The two entrance aperture zipper halves 36A, 36B cooperatively engage one another, through the use of a zipper slider 44 to facilitate securing the sleeping bag 10 in a closed position as shown in FIG. 4. The zipper halves 36A, 36B do not run along the lower end 14 of the sleeping bag, or along the opposite side 17 of the sleeping bag, and thus the bottom portion 11 of the sleeping bag 10 defines an enclosure. More particularly, both entrance aperture zipper halves 36A, 36B terminate at a point 43 which notionally separates the enclosed bottom portion 11 of the sleeping bag 10 from the upper portion defined by the extent of the entrance aperture zipper 36. Preferably, as shown in FIG. 1, the first entrance aperture zipper half 36A is recessed between the first draft tube 30 and the overlapping outer edge of the main sheet 28 and the second entrance aperture zipper half 36B is recessed between the second draft tube 32 and the overlapping outer edge of the main sheet 28.

A zipper slider flap 38 having Velcro®-type hook-and-loop strips 40 and 41 assists in retaining the zipper slider 44 when the two entrance aperture zipper halves 36A, 36B are secured to one another. When the sleeping bag 10 is in a partially open position and the zipper slider flap 38 is not in use, the zipper slider flap 38 can be folded over on itself and secured in a folded position by securing Velcro-type hook-and-loop strip 40 to complementary Velcro-type hook-and-loop strip 41.

Preferably, the main sheet 28 comprises an outer shell and an inner shell with a layer of insulation disposed therebetween, and still more preferably, a differential cut is used, wherein the inner shell is sewn smaller than the outer shell, permitting the insulation to loft more effectively and thereby improving the insulating properties of the sleeping bag 10. Any suitable fabrics and insulation types may be used.

The draft tubes 30, 32 preferably each comprise an insulation-filled fabric tube; any suitable fabrics and insulation types may be used. Similarly, the draft collar 34 also preferably comprises an insulation-filled fabric tube. Preferably, the draft collar 34 and the draft tubes 30, 32 are secured to the main sheet 28 by stitching of only the inside layer thereof to only the inside layer of the main sheet 28 (not the entire main sheet 28) to reduce heat loss.

The ends of the draft collar 34 are fitted with complementary Velcro-type hook-and-loop fastener strips 48. The draft collar 34 also has a drawstring or shock cord 50 disposed at the longitudinal center thereof, which can be tightened (or loosened) by way of cord lock 52 to divide the draft collar 34 into two longitudinal halves.

FIG. 1A is a cross-sectional view along the bottom portion 16 of the sleeping bag 10, showing attachment of the draft collar 34 to the main sheet 28 of the sleeping bag 10. The draft collar 34 may be attached by sewing or similar threading. On the interior side 39 of the draft collar 34 (i.e. facing the lower end 14) is located a first layer attachment zipper half 72. A cover flap 33 is disposed between the draft collar 34 and the first layer attachment zipper half 72 and the second layer attachment zipper half 72, that is the cover flap 33 extends along both the first half 16 and the second half 18. On the exterior side 37 of the draft collar 34 (i.e. facing the entrance end 12) is located a first member attachment zipper half 73, which extends across the first opposed half 16 at the entrance end 12.

A plurality of loops 56 are secured to the outer periphery of both halves 16, 18 of the sleeping bag 10, and may be used, for example, to secure bungee straps (not shown) to the sleeping bag 10. As shown in FIG. 1, a loop 64 is secured to the lower end 14 of the sleeping bag 10, to assist in hanging the sleeping bag 10.

Attachment of a detachable layer 100 to the sleeping bag 10 is shown in FIG. 2. Analogously to the sleeping bag 10, the detachable layer 100 has an entrance end 112 corresponding generally to the entrance end 12 of the sleeping bag 10 and a lower end 114 corresponding generally to the lower end 14 of the sleeping bag 10 (see FIG. 4). The detachable layer 100 has a shape corresponding generally to the shape of the sleeping bag 100, so that it will fit within the sleeping bag 10. The detachable layer 100 may be made from any suitable material or combination of materials. As with the main sheet 28 of the sleeping bag 10, a differential cut is preferably used, wherein the sheet that will be the inner shell is sewn smaller than the sheet that will be the outer shell, so as to permit the insulation to loft more effectively.

The detachable layer 100 defines an enclosure, and is inserted into the sleeping bag 10 by pushing the lower end 114 into the lower end 14 of the sleeping bag 10 as shown by arrow 115. The detachable layer 100 is open at its entrance end 112, thus defining an entrance aperture by which a user can enter the detachable layer 100. The entrance aperture at the entrance end 112 of the detachable layer 100 is extended by a slit 49 running along the side of the detachable layer 100 so that the detachable layer 100 is substantially coterminous with the sleeping bag 10.

The detachable layer 100 has two layer zipper halves 172, 174 running along its edges at its entrance end 112. The layer zipper half 172 cooperates with the layer attachment zipper half 72 on the sleeping bag 10 to secure the detachable layer 100 to the sleeping bag 10 as shown by arrow 117. Similarly, the layer zipper half 174 cooperates with the layer attachment zipper half 74 on the sleeping bag to further secure the detachable layer 100 to the sleeping bag 10. The layer zipper halves 172, 174 are on opposite edges of the entrance aperture of the detachable layer 100 corresponding to the edges of the sleeping bag 10 on which the layer attachment zipper halves 72, 74 are located.

Referring to FIG. 2A, when the detachable layer 100 is inserted into the sleeping bag 10 the layer zipper halves 172, 174 on the detachable layer 100 are aligned with the corresponding layer attachment zipper halves 72, 74 on the sleeping bag 10 such that the detachable layer 100 is enveloped within the sleeping bag 10 and such that the entrance aperture of the detachable layer 100 is aligned with the entrance aperture of the sleeping bag 10 and the slit 49 is aligned with the entrance aperture zipper 36.

FIG. 3 shows a detailed view of the bottom portion 99 of the detachable layer 100 attached to the sleeping bag 10 by mating the layer attachment zipper half 72 on the bottom half 16 of the sleeping bag 10 with the layer zipper half 172 from the bottom portion 99 of the detachable layer 100.

Also shown in FIG. 3 is a more detailed view of a hold-down flap 82 secured to the main sheet 28 (not shown in FIG. 3). One hold-down flap 82 is disposed adjacent each end of the draft collar; only one hold-down flap is shown in FIG. 3. When the first layer attachment zipper half 72 is mated to the layer zipper half 172 to join the bottom half 16 of the sleeping bag 10 with the bottom half 99 of the detachable layer 100 the zipper slider 80 is at the outside end of the zipper halves 172, 72. Once both the upper and lower portions of the detachable layer 100 are secured to the first and second halves 16, 18, respectively, of the sleeping bag 10 (by way of mating zipper halves 72,172 and 74, 174 with one another), the hold-down flap 82 at each end of the draft collar 34 is folded inwardly to cover its respective zipper slider. The cover flap 33, which has Velcro-type hook-and-loop fasteners 35 at each end, can then be folded down over the zipper sliders 80 and the zipper halves 72, 172 and 74, 174 and secured to the hold-down flaps 82 by way of complementary Velcro-type hook-and-loop fasteners 83 on the hold-down flaps 82. This folded down position is shown in FIG. 3A.

The detachable layer 100 may be completely enclosed in the sleeping bag 10 when the sleeping bag 10 is closed, as shown in FIG. 4.

Detachable sleeping bag members, including a detachable pillow sleeve 500 and a detachable hood 600, may be selectably releasably secured to the sleeping bag as described below. Moreover, a detachable pillow sleeve 500 may be selectably releasably secured to the sleeping bag 10, and a detachable hood 600 may be selectably releasably secured to the detachable pillow sleeve and hence to the sleeping bag 10, as described below.

Referring to FIG. 5, a first member attachment zipper half 73 extends across the first opposed half 16 at the entrance end 12, and a second member attachment zipper half 75 extends across the second opposed half 18, also at the entrance end 12. Specifically, the first member attachment zipper half 73 is attached at the seam where the draft collar 34 attaches to the main sheet 28 on the first half 16, and the second member attachment zipper half 75, of the same length and opposed to the first member attachment zipper half 73, is located at the seam where the draft collar 34 joins the sleeping bag 10 on the second half 18. Thus, the member attachment zipper halves 73, 75 are on the opposite side of the draft collar from the layer attachment zipper halves 72, 74. As can be seen in the Figures, the term “at the entrance end 12”, when used to describe the location of the member attachment zipper halves 73, 75, should not be construed as requiring the member attachment zipper halves 73, 75 to be at the outermost edge of the entrance end 12, and the member attachment zipper halves 73, 75 may be located inwardly of the entrance aperture without departing from the scope of the present invention.

A detachable pillow sleeve 500 is shown in FIGS. 5, 5A, 6, 7 and 9A and 9B. The detachable pillow sleeve 500 may have a generally rectangular shape with four edges and two opposed faces. The detachable pillow sleeve 500 has a pillow sleeve attachment zipper half 573 extending along one edge of the detachable pillow sleeve 500. The pillow sleeve attachment zipper half 573 can mate with both the first member attachment zipper half 73 as shown, and can also mate with the second member attachment zipper half 75. Thus, the pillow sleeve 500 can be selectably removably attached to either the first half 16 of the sleeping bag 10 (as shown in FIG. 5A), or the second half 18 of the sleeping bag 10 (not shown). The pillow sleeve 500 also has an access zipper 552 which allows the pillow sleeve 500 to receive cushioning, such as a pillow 604 or rolled-up clothing. The access zipper 552 comprises two opposed zipper halves, and is provided with a zipper slider 80 and a receiving end 81.

The detachable pillow sleeve 500 may be made of any suitable material, including silk charmeuse. The access zipper 552 may be replaced with any other suitable type of fastener(s), such as snap-fasteners or complementary Velcro-type hook-and-loop strips, for retaining a pillow 604 (see FIG. 6).

The detachable pillow sleeve 500 also has a first hood attachment zipper half 556 adjacent and substantially parallel to the pillow sleeve attachment zipper half 573, for selectably removably receiving a detachable hood.

FIGS. 5, 5B, 6, 7 and 9A and 9B show a detachable hood 600 having a second hood attachment zipper half 656 extending along a base edge (that is, the edge opposed to the main body of the hood) of the detachable hood 600. The second hood attachment zipper half 656 can mate both with the first hood attachment zipper half 556 on the pillow sleeve 500, and also with either of the first member attachment zipper half 73 and with the second member attachment zipper half 75. Thus, the detachable hood 600 can be selectably removably attached to the pillow sleeve 500 and thus indirectly secured to the sleeping bag 10, as shown in FIG. 6, or can be selectably removably attached directly to either the first half 16 of the sleeping bag 10 (as shown in FIG. 5B), or the second half 18 of the sleeping bag 10 (not shown).

The detachable hood 600 defines an interior 602 and includes a visor tube 630, and has a shock cord tunnel 624 running along the bottom of the visor tube 630 which receives two shock cords 620, which can be adjusted by way of shock cord locks 622. Alternatively, the shock cord tunnel 624 may be disposed within the visor tube 630. The detachable hood 600 and visor tube 630 may be made from any suitable materials.

When the detachable pillow sleeve 500 or the detachable hood 600, or both of them, are attached at the entrance end 12 of the sleeping bag 10, it (or they) project outwardly, away from the entrance end 12 of the sleeping bag 10, as shown in the Figures.

The member attachment zipper halves 73, 75 on the sleeping bag 10, as well as the first hood attachment zipper half 556 on the pillow sleeve 500, are provided with a zipper slider 80 and a receiving end 81. The receiving ends 81 of the first and second member attachment zipper halves 73, 75 can receive a pin 83 on either of the pillow sleeve attachment zipper half 573 and the second hood attachment zipper half 656. The receiving end 81 of the first hood attachment zipper half 556 can receive the pin 83 on the second hood attachment zipper half 656. The operation of zippers is well known to a person of ordinary skill in the art and is not further described.

FIG. 6A shows a detailed view of the relevant zippers when the detachable pillow sleeve 500 removably attached to the first half 16 of the sleeping bag 10 and the detachable hood 600 removably attached to the detachable pillow sleeve 500. The first member attachment zipper half 73 is mated with the pillow sleeve attachment zipper half 573 on the detachable pillow sleeve 500. A flap of fabric 650 covers the mated first and second hood attachment zipper halves 556 and 656.

Referring to FIG. 7, it may be desirable to attach the detachable hood 600 or the detachable pillow sleeve 500 or both onto the detachable layer 100 when a lighter cover is required (assuming the detachable layer 100 is a lighter cover than the sleeping bag 10). The detachable pillow sleeve 500 or the detachable hood 600 may be attached to either the layer zipper half 172 on the bottom side or the layer zipper half 174 on the top side of the detachable layer 100. Thus, the layer zipper halves 172, 174 function as member attachment zipper halves in this context. In FIG. 7, the detachable pillow sleeve 500 is shown attaching to the layer zipper half 172 on the detachable layer 100. The detachable hood 600 is shown attaching to the detachable pillow sleeve 500. When used alone, the detachable layer 100 may be considered to be a sleeping bag in and of itself.

Because both the first half and the second half of the sleeping bag is provided with member attachment zipper halves, a user of a sleeping bag system incorporating a sleeping bag, pillow sleeve and/or hood according to an aspect of the present invention can configure the sleeping bag so that the entrance aperture zipper or side slit thereof is on either the left or right side, and still have the pillow sleeve and/or hood facing up.

FIG. 8 shows an embodiment in which two sleeping bags 10A, 10B are attached side-by-side, and FIG. 9A shows the two sleeping bags 10A, 10B with pillow sleeves 500 and hoods 600 attached. In FIG. 9A, the same reference numerals are used to describe features identical to those described elsewhere. The second entrance aperture zipper half 36B of the first sleeping bag 10A attaches to the first entrance aperture zipper half 36A of a second sleeping bag 10B. Similarly, the first entrance aperture zipper half 36A of the first sleeping bag 10A attaches to the second entrance aperture zipper half 36B of the second sleeping bag 10B (not shown). The result is that the first half 16 of the second sleeping bag 10B faces the same direction as the second half 18 of the first sleeping bag 10A to which it is attached. Such a configuration may be suitable, for example, for two people to sleep together, and allows the bottom portion 14 of each sleeping bag 10A, 10B to remain separate with the sides 15 defining a boundary, while the top portions of each sleeping bag 10A, 10B unite to become a single compartment. Because the detachable pillow sleeves 500 (and similarly the detachable hoods 600) can attach to either of the first and second member attachment zipper halves 73, 75, the two sleeping bags 10A, 10B may both have detachable pillow sleeves 500 or detachable hoods 600, or both, attached to the same surface (i.e. facing in the same direction).

As shown in FIG. 9B, as long as the entrance aperture zippers on each of the two sleeping bags 10AA, 10BB are of equal length, sleeping bags of dissimilar length may be joined together using the above described technique. Thus, FIG. 9B shows a first sleeping bag 10AA having a first length and a second sleeping bag 10BB having a second length that is different from the first length. In FIG. 9B, the same reference numerals are used to describe features identical to those described elsewhere. Each sleeping bag 10AA, 10BB comprises first and second opposed sleeping bag halves 16, 18 defining respective sleeping compartments therebetween. Each sleeping bag 10AA, 10BB has an entrance aperture at an entrance end thereof, and each entrance aperture opens into the respective sleeping compartment. Each sleeping bag 10AA, 10BB further comprises an entrance aperture zipper 36 comprising a first entrance aperture zipper half 36A extending at least partially along an edge of the first opposed half 16 and a second entrance aperture zipper half 36B extending at least partially along an edge of the second opposed half 18. The first and second entrance aperture zipper halves 36A, 36B mate with one another for selectably enlarging and constricting the entrance aperture. Each entrance aperture zipper 36 is of equal length, and the first entrance aperture zipper half 36A of each sleeping bag 10AA, 10BB mates with the second entrance aperture zipper half 36B of the other sleeping bag 10AA, 10BB.

Various sizes of sleeping bags may be constructed in accordance with aspects of the present invention. The chart below shows various exemplary combinations of length and width for a sleeping bag, such as sleeping bag 10, which can accommodate a range of human physiques (all numbers are approximate). More particularly, the chart below provides for twelve different sizes of sleeping bags, as any particular one of four lengths may be freely combined with any particular one of three widths.

WIDTH SMALL MEDIUM LARGE (Shoulder & (up to) (up to) (up to) Hip 60″/152.4 70″/177.8 80″/203.2 LENGTH Circumference) cm cm cm SHORT 5′6″/167.64 cm SL/SW SL/MW SL/LW REGULAR 5′10″/177.8 cm RL/SW RL/MW RL/LW LONG 6′2″/187.96 cm LL/SW LL/MW LL/LW X-LONG 6′6″/198.12 cm XLL/SW XLL/MW XLL/LW

Zippers used in accordance with aspects of the present invention may be made from any suitable material, including metal, plastic and nylon. Nylon and plastic zippers may advantageously be used because they are resistant to corrosion. In addition, double-slider arrangements, wherein two zipper sliders instead of one are used to enable a zipper to be unzipped from either end, may also be used.

Reference has been made herein to the use of Velcro-type hook-and-loop fastening arrangements. Hook-and-loop fasteners made by entities other than Velcro Industries B.V. and its affiliates may also be used, subject to any relevant intellectual property rights, without departing from the scope of the present invention.

One or more currently preferred embodiments have been described by way of example. It will be apparent to persons skilled in the art that a number of variations and modifications can be made without departing from the scope of the invention as defined in the claims. More particularly, it will be appreciated that various individual features from different exemplary embodiments described herein may be combined to produce an embodiment not explicitly shown or described, without departing from the scope of the present invention. 

1. A sleeping bag, comprising: first and second opposed halves defining a sleeping compartment therebetween; an entrance aperture at an entrance end of the sleeping bag, the entrance aperture opening into the sleeping compartment; a first member attachment zipper half extending across the first opposed half at the entrance end; a second member attachment zipper half extending across the second opposed half at the entrance end.
 2. The sleeping bag of claim 1, wherein a draft collar extends across the entrance aperture inwardly of the entrance end and the first member attachment zipper half and the second member attachment zipper half are located adjacent the draft collar, between the draft collar and the entrance end.
 3. A sleeping bag system, comprising: a sleeping bag according to claim 1; and a detachable pillow sleeve, the detachable pillow sleeve having: a pillow sleeve attachment zipper half extending along one edge of the detachable pillow sleeve and mating with the first member attachment zipper half and with the second member attachment zipper half; and a first hood attachment zipper half adjacent and substantially parallel to the pillow sleeve attachment zipper half.
 4. A sleeping bag system according to claim 3, further comprising a detachable hood, the detachable hood having a second hood attachment zipper half extending along a base edge of the detachable hood, the second hood attachment zipper half mating with the first hood attachment zipper half and with the first member attachment zipper half and with the second member attachment zipper half.
 6. A sleeping bag according to claim 1, further comprising an entrance aperture zipper comprising a first entrance aperture zipper half extending at least partially along an edge of the first opposed half and a second entrance aperture zipper half extending at least partially along an edge of the second opposed half, the first and second entrance aperture zipper halves mating with one another for selectably enlarging and constricting the entrance aperture.
 7. A detachable pillow sleeve, the detachable pillow sleeve having a pillow sleeve attachment zipper half extending along one edge thereof, and a hood attachment zipper half adjacent and substantially parallel to the pillow sleeve attachment zipper half.
 8. A detachable pillow sleeve according to claim 7, wherein cushioning is disposed inside the detachable pillow sleeve.
 9. A sleeping bag system, comprising: a first sleeping bag having a first length; a second sleeping bag having a second length that is different from the first length; each sleeping bag comprising first and second opposed sleeping bag halves defining respective sleeping compartments therebetween, each sleeping bag having an entrance aperture at an entrance end thereof, each entrance aperture opening into the respective sleeping compartment, each sleeping bag further comprising an entrance aperture zipper comprising a first entrance aperture zipper half extending at least partially along an edge of the first opposed half and a second entrance aperture zipper half extending at least partially along an edge of the second opposed half, the first and second entrance aperture zipper halves mating with one another for selectably enlarging and constricting the respective entrance apertures; each entrance aperture zipper being of equal length; and each first entrance aperture zipper half mating with the second entrance aperture zipper half of the other sleeping bag.
 10. A sleeping bag system, comprising: a sleeping bag, comprising: first and second opposed halves defining a sleeping compartment therebetween; a sleeping bag entrance aperture at an entrance end of the sleeping bag, the sleeping bag entrance aperture opening into the sleeping compartment; a first member attachment zipper half extending across the first opposed half at the entrance end; a second member attachment zipper half extending across the second opposed half at the entrance end; a first layer attachment zipper half extending across the first opposed half at the entrance end, inwardly of the first member attachment zipper half; a second layer attachment zipper half extending across the second opposed half at the entrance end, inwardly of the second member attachment zipper half; and a sleeping bag entrance aperture zipper comprising a first sleeping bag entrance aperture zipper half extending at least partially along an edge of the first opposed half and a second sleeping bag entrance aperture zipper half extending at least partially along an edge of the second opposed half, the first and second sleeping bag entrance aperture zipper halves mating with one another for selectably enlarging and constricting the sleeping bag entrance aperture; a detachable pillow sleeve, the detachable pillow sleeve having: a pillow sleeve attachment zipper half extending along one edge of the detachable pillow sleeve and mating with the first member attachment zipper half and with the second member attachment zipper half; and a first hood attachment zipper half adjacent and substantially parallel to the pillow sleeve attachment zipper half; a detachable hood, the detachable hood having a second hood attachment zipper half extending along a base edge of the detachable hood, the second hood attachment zipper half mating with the first hood attachment zipper half and with the first member attachment zipper half and with the second member attachment zipper half, and a detachable layer, the detachable layer: defining an enclosure having a layer entrance aperture that is extended by a slit along a side of the detachable layer; being sized to fit within the sleeping compartment of the sleeping bag so as to be substantially coterminous with the sleeping bag; having first and second layer zipper halves extending along opposed edges of the layer entrance aperture, the first layer zipper half mating with the first layer attachment zipper half and the second layer zipper half mating with the second layer attachment zipper half; wherein, when the first layer zipper half is mated with the first layer attachment zipper half and the second layer zipper half is mated with the second layer attachment zipper half, the layer entrance aperture is aligned with the sleeping bag entrance aperture and the slit extending the layer entrance aperture is aligned with the sleeping bag entrance aperture zipper.
 11. The sleeping bag system of claim 10, wherein the first and second layer zipper halves each also mate with the pillow sleeve attachment zipper half and the second hood attachment zipper half. 